Isolated perfused liver model: the rat and the guinea pig compared

Abstract

Abstract Objective Although the rat is the most commonly used species for the study of hepatic metabolism, the physiology of the guinea pig is closer to human physiology. We compared the model of isolated perfused guinea pig liver with the classic model of isolated perfused rat liver, especially with respect to amino acid metabolism. Methods After validation of an anesthetic mixture of ketamine, diazepam, and xylazine for the guinea pig, isolated perfused livers were harvested for both species. Three groups of animals were compared for the study of liver metabolic fluxes: 6-wk-old male Sprague-Dawley rats (R; 230 ± 10 g, n = 5), young male Hartley guinea pigs (YG; 223 ± 8 g, n = 6) matched to rats by liver weight, and adult male Hartley guinea pigs (AG; 389 ± 5 g, n = 6) matched to rats by age. Results (mean ± standard error of the mean) were compared by analysis of variance and Newman-Keuls tests. Results Both models displayed a satisfactory hepatic viability, but differences were noted, with higher portal flows (R: 3.1 ± 0.3 versus YG: 4.5 ± 0.3 and AG: 4.2 ± 0.3 mL · min −1 · g −1 ; P −1 · g −1 ; P P P P Conclusion Our results indicate that the isolated perfused guinea pig liver is a suitable model for the study of hepatic metabolism.